How do I get a Theta V stream into OBS on a Jetson Nano?


I’m trying to get a livestream from my Theta V camera into OBS running on an Nvidia Jetson Nano, so that I can use the OBS NDI Plugin and send the video over NDI to another computer.

So far:

  1. I am successfully getting a 4k stream from my Theta V into my Jetson nano by following the instructions here. Specifically, I’m able to run the ./gst_viewer sample app and see the live stream with reasonably low latency.
  2. After installing v4l2-loopback, I also see a /dev/video0 device listed


  1. I’m still not able to see the device in OBS as a viable/available video device.
  2. FWIW, a simple pipeline like gst-launch-1.0 v4l2src ! xvimagesink also does not work.

Is there something else that I need to do to see the stream as a viable video device (like a USB webcam) so that I can get it into OBS?

Thank you,


It should appear as a USB webcam. There are some example here:

This video playlist may help.

This video covers running VLC, gstreamer (gst-launch-1.0) and others on a Jetson Nano.

when you run lsmod, can you see the vl42loopback module?

$ lsmod
Module                  Size  Used by
bnep                   16562  2
zram                   26166  4
overlay                48691  0
spidev                 13282  0
v4l2loopback           37383  0
nvgpu                1579891  18
bluedroid_pm           13912  0
ip_tables              19441  0
x_tables               28951  1 ip_tables

Did you try manually inserting the module?

$ sudo modprobe v4l2loopback
$ cd path_to_gst_loopback_directory
$ ./gst_loopback
$ cvlc v4l2:///dev/video2

I don’t know if it is necessary, but you could try this pipeline as a test.

$ gst-launch-1.0 v4l2src device=/dev/video2 ! video/x-raw,framerate=30/1 ! xvimagesink
Setting pipeline to PAUSED ...
Pipeline is live and does not need PREROLL ...
Setting pipeline to PLAYING ...
New clock: GstSystemClock

Can you see the device with v4l2-ctl ?


$ v4l2-ctl --list-formats-ext --device  /dev/video2
    Type: Video Capture

    [0]: 'YU12' (Planar YUV 4:2:0)
        Size: Discrete 1920x960
            Interval: Discrete 0.033s (30.000 fps)

Thank you for your help; I have reviewed those videos and I believe I’m on the same page. Here is what I get from the diagnostic commands you provided:

I can see the Theta with lsusb

ali@ali-nano:~/Documents/Dev/libuvc-theta-sample/gst$ lsusb
Bus 002 Device 002: ID 0bda:0411 Realtek Semiconductor Corp. 
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 046d:c52b Logitech, Inc. Unifying Receiver
Bus 001 Device 015: ID 05ca:2712 Ricoh Co., Ltd 
Bus 001 Device 002: ID 0bda:5411 Realtek Semiconductor Corp. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Running ./gst_viewer works; I can see my video stream from the theta.

I also see /dev/v4l2loopback and /dev/video0:

ali@ali-nano:~/Documents/Dev$ ls /dev/v*
/dev/v4l2loopback  /dev/vcs1  /dev/vcs3  /dev/vcs5  /dev/vcsa   /dev/vcsa2  /dev/vcsa4  /dev/vcsa6  /dev/video0
/dev/vcs           /dev/vcs2  /dev/vcs4  /dev/vcs6  /dev/vcsa1  /dev/vcsa3  /dev/vcsa5  /dev/vhci

Did you try manually inserting the module?

I did, but I get an error below:

ali@ali-nano:~/Documents/Dev/libuvc-theta-sample/gst$ ls
gst_loopback  gst_viewer  gst_viewer.c  gst_viewer.o  Makefile  thetauvc.c  thetauvc.h  thetauvc.o
ali@ali-nano:~/Documents/Dev/libuvc-theta-sample/gst$ sudo modprobe v4l2loopback
ali@ali-nano:~/Documents/Dev/libuvc-theta-sample/gst$ ./gst_loopback 
start, hit any key to stop
Error: Cannot identify device '/dev/video1'.

I read that the sample assumes I have another camera; I do not; I expect the Theta to show up on /dev/video0.

when you run lsmod , can you see the vl42loopback module?

Yes I can:

ali@ali-nano:~/Documents/Dev/libuvc-theta-sample/gst$ lsmod
Module                  Size  Used by
uvcvideo               90357  0
v4l2loopback           42895  0
fuse                  103841  3
bnep                   16562  2
xt_conntrack            3609  1
ipt_MASQUERADE          2346  1
nf_nat_masquerade_ipv4     3111  1 ipt_MASQUERADE
nf_conntrack_netlink    28859  0
nfnetlink               7959  2 nf_conntrack_netlink
xt_addrtype             3670  2
iptable_filter          2481  1
iptable_nat             2882  1
nf_conntrack_ipv4      11992  2
nf_defrag_ipv4          1836  1 nf_conntrack_ipv4
nf_nat_ipv4             6712  1 iptable_nat
nf_nat                 20406  2 nf_nat_masquerade_ipv4,nf_nat_ipv4
nf_conntrack          105820  6 nf_conntrack_ipv4,nf_conntrack_netlink,nf_nat_masquerade_ipv4,xt_conntrack,nf_nat_ipv4,nf_nat
br_netfilter           16250  0
zram                   26166  4
overlay                48691  0
hid_logitech_hidpp     22721  0
hid_logitech_dj        13813  0
spidev                 13282  0
userspace_alert         5665  0
nvgpu                1580772  32
bluedroid_pm           13912  0
ip_tables              19441  2 iptable_filter,iptable_nat
x_tables               28951  5 ip_tables,iptable_filter,ipt_MASQUERADE,xt_addrtype,xt_conntrack

Can you see the device with v4l2-ctl?

This is what I get; does not look like your output.

ali@ali-nano:~/Documents/Dev/libuvc-theta-sample/gst$ v4l2-ctl --list-formats-ext --device /dev/video0

try this pipeline as a test.

This pipeline does not work for me; gst-launch quits:

ali@ali-nano:~/Documents/Dev/libuvc-theta-sample/gst$ gst-launch-1.0 v4l2src device=/dev/video0 ! video/x-raw,framerate=30/1 ! xvimagesink
Setting pipeline to PAUSED ...
Pipeline is live and does not need PREROLL ...
ERROR: from element /GstPipeline:pipeline0/GstV4l2Src:v4l2src0: Internal data stream error.
Additional debug info:
gstbasesrc.c(3055): gst_base_src_loop (): /GstPipeline:pipeline0/GstV4l2Src:v4l2src0:
streaming stopped, reason not-negotiated (-4)
ERROR: pipeline doesn't want to preroll.
Setting pipeline to PAUSED ...
Setting pipeline to READY ...
Setting pipeline to NULL ...
Freeing pipeline ...

I also tried a different USB webcam and confirmed that I can capture it in OSB, or via gstreamer.

What do you think?


In the source code, of gst_viewer.c, specify /dev/video0 recompile.

Please report back on results either way. You’re providing excellent information to help us identify the problem.

I made the change you recommended to gst_viewer.c and recompiled with and rebuilt with make.
I don’t perceive any difference:

What I did:

  • made the change to video0 in gs_viewer.c
  • ran make
  • manually loaded the module with sudo modprobe v4l2loopback

What I see is:

  • gst_viewer still works; I can see the video stream on screen
  • both /dev/v4l2loopback and /dev/video0 are present
  • ls -1 /sys/devices/virtual/video4linux returns: video0


  • The gst-launch command still stops as before
  • v4l2-ctl --list-formats-ext --device /dev/video0 still returns ioctl: VIDIOC_ENUM_FMT as before
  • OBS still does not see the video device

Another test I performed was to run libuvc-theta-sample/gst/gst_loopback:

ali@ali-nano:~/Documents/Dev/libuvc-theta-sample/gst$ ./gst_loopback 
start, hit any key to stop
NvMMLiteOpen : Block : BlockType = 261 
NVMEDIA: Reading vendor.tegra.display-size : status: 6 
NvMMLiteBlockCreate : Block : BlockType = 261 
Error: Internal data stream error.

Something I have noticed all along is that the OBS recognizes the microphone on the Theta V and I do get sound input; but no video.

What do you think?

I tried setting this up again on a fresh Jetson and I still have the same issue.
When I run loopback, either with /dev/video0 or /dev/video1, I get:

Error: Cannont identify device '/dev/video0' or video1

gst_viewer continues to work; my theta is streaming fine.

Any ideas what may be my issue?

Is there a ppa binary of OBS for the Jetson Nano that I can try?



working on /dev/video0 with vlc

working on /dev/video0 with ffplay (ffmpeg)

Verify that v4l2loopback is running in the kernel

If it is not running, install and load it into the kernel.

It looks like nickel110 updated the README for gstthetauvc with a link to the obs-gstreamer plug-in.

1 Like

Thank you for your reply @craig , I really appreciated it.

It’s strange:

The device is there:

ali@ali-nano:~/Documents/Dev/libuvc-theta/build$ ls -1 /sys/devices/virtual/video4linux

loopback is running:

ali@ali-nano:~/Documents/Dev/libuvc-theta/build$ sudo lsmod |grep v4l2
v4l2loopback 42895 0

I’m using several apps to test if the device is available and none of them see it; OBS is one, but i’m also trying with Cheese (sudo apt-get install cheese) which is a simple webcam viewer; no luck on any of them.

I can still run the stream viewer and see the stream…

Here is a curious observation:
In OBS, i’m able to see the audio signal from the Theta, but no video source is recognized!

Is there a way to get info about the video0 device which is there to see what is wrong with it?